Alpha-Omega
by R3QU13M
Summary: (Alternate Timeline) a day after defeating the collectors, the normandy was contacted by oriana who was kidnapped and bought to a cerberus facility. when they arrived at the facility and rescued oriana, they discovered that in the facility lies the most powerful biotic in the universe; which is also the child of miranda and shepard. OC-Arthur L. Shepard
1. ALPHA-OMEGA

**Alpha-Omega**

**Note: Shepard has the default face and is a Spacer and Ruthless, also I've made changes from the game. This is an alternate timeline**

A day after defecting from Cerberus and destroying the collectors, Commander John Shepard; The resurrected savior of the council and now the leader of the defected Lazarus cell; is surveying the galaxy map for possible the next destination. Shepard thinks that the illusive man is searching for the cell so he told everyone to be on alert. He looked around the entire CIC, the entire crew is here .Suddenly someone interrupted him.

"Shepard, we're intercepting a Cerberus transmission" says a feminine voice with her Omni-tool active with the intercepted transmission, and then all of the crew with the exception of joker looked at her.

He looked at her; it was his love, Miranda Lawson who is on the other side of the galaxy map "is it from the illusive man?" Shepard questioned "no Shepard, but from someone else" Miranda replied. Shepard wondered what could the transmission be "put it on all speakers" he said

Miranda uses her Omni-tool to place the transmission on all speakers and then a voice of a young woman with a voice of a teenager is heard talking and panting nervously, gunshots and screams are also being heard, Miranda and Miranda got scared and nervous when the voice said her name.

"Commander Shepard this is Oriana Lawson, I've been abducted by Cerberus to their facility called the Repository which is in the orbit of Patatanlis of the Han System, but hours later half of them have gone mad and started killing everyone. Go there and find this facility and you might want to explore this place, I've heard of some of highly classified Intel is in here-"the transmission was cut by a static. Miranda opened her Omni-tool and starts to ask if her sister can hear her "Ori?...Ori can you hear me!" this time it is Shepard who opens his Omni-tool "Joker enter the relay and head to the Han system, now and everyone, gear up" Shepard said to everyone before heading to the Weapons locker along with his team. Once there he heads to his locker to grab his weapons which is a M-96 Mattock and M-5 Phalanx, then he goes to his cabin where his armor locker is and puts on his Blood Dragon Armor then he felt the ship shakes meaning that the Normandy entered the Mass relay. Shepard got a little mad at joker for not telling him or any of the crew.

After the travel, the Normandy arrived at the facility and stopped with its right side facing it, Shepard ordered Kasumi, Thane, Garrus and Miranda to come with him in the rescue operation and meet him at the hangar where they ride a Kodiak to land on the facility. Minutes later they found a closed docking area which made Shepard called legion.

"Legion can you hack the facilities system to open that door?" Shepard asked the Geth

"Possible Shepard commander, but it might take some time due to Cerberuses secure systems" the geth said as he begins to hack the systems.

Not far from their position a Cerberus trooper sees the Normandy "this is T-Z14, the Normandy I'm seeing the Normandy not far from my location, awaiting orders" "this is apex, 2 Fighter squadrons are on their way to your position, stand by for new orders" the commander radioed out.

In the Normandy legion is having a difficulty of passing through the security systems on the facility. But still successfully hacks them and he opens the doors.

"Alright let's go" he said as the Kodiak begins to enter the facility. Back at the Normandy, EDI appears on the bridge where the others are.

"Joker, Cerberus forces Detected south east of our position" EDI said as joker and grunt leaned to the nearest mirror in that position and saw the fighters "shit, hold on everybody" he moves the Normandy away from the fighters before they could fire at them.

Inside the facility, Shepard and his squad disembarks from the Kodiak and starts to move deeper in the facility, they walked the nearest stairs to reach the door. Once there Shepard was contacted by joker "uhh… commander, Cerberus fighters are attacking us" "Joker destroy them, then patrol the entire facility and open fire at any Cerberus ship you see" he gave his orders to joker, then he contacts legion "legion, hack the security camera's in here to give us advantage" "Yes commander" the synthetic said

The two fighters kept firing their flak cannons at the Normandy which always avoids all shots. Joker was surprised about its heavy firepower despite its size.

"Hey EDI, can you give me some information about those" joker said referring to the fighters behind the Normandy. EDI appears "Searching Cerberus files, F-54 Morningstar, agile, fast and fuel efficient, has onboard VI for Combat assistance" EDI explained to joker. The GARDIAN lasers aimed at the fighters and opens fire at them, but their fast and agile bodies allows them to avoid sudden deaths from the lasers. It was very difficult for them to destroy "damn these things are starting to piss me off" joker said in irritation.

After opening the door, Shepard and the team walks through a large hall, which has barricades, blood and dead bodies of scientists. Shepard looked up and saw an elevator in a balcony on the right side of their position and stairs in its left. He signals them to follow him as he heads to the stairs and steps goes up where the elevator is. When he was about to press the button to open the elevator, legion contacts him through the Omni-tool "Shepard commander we have located the human you call Oriana" legion said. Miranda approached Shepard's Omni-tool "where?" she asked.

"Three floors above you, she is fending off Cerberus troops with some scientists and engineers" legion said.

With that Shepard presses the open button of the elevator and enters it with his squad, once inside he presses buttons again which closes the doors of the elevator and goes to the designated floor. They all looked at the number 1 on the top of the door, in a second it becomes two, Shepard looks at his squad, he can see that they are becoming more nervous by each number but Miranda remained focused and fearless because they're rescuing her sister. When it becomes four, the door slowly opens revealing Cerberus troops consisting of 15 assault troopers and 3 YMIR Mechs attacking Oriana along with the scientist and engineers who are in covering in the barricades, they saw Oriana shooting Cerberus troops using an M-25 Hornet submachine gun. Not being noticed yet Shepard ordered garrus, kasumi and thane to take cover on the right wall while he and Miranda take cover at the left wall.

Oriana was shooting as many Cerberus troops as possible until her weapon has runs out of ammo. She quickly takes cover to avoid the bullet that was about to kill her. She can hear their footsteps getting closer at her position, it was hopeless, she thought she was about to die. However she hears a trooper fall to the ground after being shot and gunfire was heard again but she saw no bullets passing their position which means that they're fighting someone else. She and the others slowly raises her head only to see the YMIR Mechs being destroyed and Cerberus troops being gunned or burned; when all were dead she saw her sister and her squad members.

"ORI!" Miranda ran to her sister and they embraced, happy to see each other alive. Shepard and the rest saw the scientist and engineers and was surprised to see that non were injured "why is Cerberus attacking all of you, shouldn't all of you working with them" Shepard starts asking questions at one of the scientist and Miranda joined in asking what do they want from her sister.

"We are called Nova; we were tasked by the illusive man on projects all about biotics" the scientist said "but our guards turned against us and we don't know why"

"Next question, what are your latest project" Shepard asked

"it was a year after Cerberus recovered your body, Project Seraphim, the creation of an L9z Implant" the scientist said

Everyone, including the Normandy was surprised that Cerberus was creating a new implant. Shepard wondered what could this implant do to a biotic "What does it do?" "We're not sure yet, but in theory that implant will make the biotic reach the edges of biotics" the scientist explained "the user will be the ultimate biotic in the universe"

Everyone can't believe what they've heard; the ultimate biotic in the universe, the ultimate dream of all. "Is it implanted on someone?" Shepard asked hoping that it won't be used by a Cerberus operative "yes, on an infant which rapidly turned 20 years old upon the installation of the implant" the scientist explained. This doesn't satisfy shepard "tell me everything about the test subject" he asked

"Under the orders of the illusive man and henry Lawson, we created an infant by merging the genetic materials of 2 powerful biotics in a tube. The illusive man believes that the child will be the symbolic figure of human ascendancy while Mister Lawson thinks it as the perfection to his genetic dynasty".

"Are you saying that my father, Henry Lawson; created another of us by getting a DNA from another person" Miranda said in anger while aiming a hornet at the scientists face "no Miss Lawson, that child is not his but yours and Commander Shepard's"

Shepard's eyes widened and while everybody's mouth dropped. A confused Miranda slowly lowers her sidearm "how? How did this happened" she questioned "Miss Lawson, in the past we secretly infiltrated the Lazarus facility to acquire genetic material from you and Commander Shepard under the orders of the illusive man and your father"

Upon learning about his child she questions the scientist about him "how is he, what is his name, is suffering in here" Miranda questioned in a worried tone. Everyone quickly notices this Miranda's new motherly personality "he's fine Miss Lawson, Arthur's fine" the scientist said referring to Shepard and Miranda's child "Arthur?" Shepard said wondering why his son was named that "it was my favorite name for a male child" Miranda said.

Suddenly a scream was heard not far from their location, the scientist and engineers were all terrified. From what has he heard that scream was on the door near them. Shepard ordered kasumi and thane to guard Oriana and the others while the rest will follow him to that door he lets the scientist to join him thinking his son knew him, when they opened it, they were in a dark balcony and when they looked below the balcony they saw dozens of Cerberus troops and 3 ATLAS Mechs aiming their weapons at a hooded human in a Cerberus phantom suit just like the one kai leng has but it has a hood

"Is that him" both Miranda questioned the scientist if that is her son, the scientist replied "yes, that's him", in the Normandy they can see what Miranda and Shepard are seeing, everyone was seeing Arthur.

Beneath his hood, Arthur can see that he is surrounded by Cerberus forces, the assault troops were all aiming their main weapons; Cerberus Harriers at him while the ATLAS Mechs will provide heavy firepower for the troops just to bring him down. However they didn't know that after months of learning and training; he developed and mastered multiple skills such as swordsmanship, stealth, martial arts, hand to hand combat, Tactical Analysis, Leadership, Enhanced intellect and Charisma.

"Stand down, kid" says the ATLAS pilot

He looked at his Katana in his Koshirae and draws it out; his katana was given by his grandfather; henry Lawson, which he permanently infused with powerful biotic energies which turned its color from silver to violet; this allows the blade to become lighter and faster. In the past observations the slicing and cutting power of the blade was so powerful it can even cut a fighter in 2 just in one slice and if given enough energy, one slice is capable of cutting an asteroid in pieces. He examined the violet surface of the blade and rested it in his shoulders.

Before anyone can react, Arthur charges at one trooper and slices him downward and in his torso rightward killing him before a second passes.

"SHIT!" says the commander in shock and fear "OPEN FIRE!" the others opens fire at Arthur, who deflects all of their bullets using his sword at light speed. Shepard, Miranda and the entire Normandy were amazed by his skills and way of fighting.

He uses his biotic powers to vanish leaving a violet flame on the floor he was. He appears above the atlas on their center and charges his right fist with biotic energy before slamming it at the atlas, which completely crushed it and sending a wave of biotic energy at the others knocking them off except the 2 remaining atlas Mechs who managed to remain standing. Arthur places his katana back to the Koshirae and his hands glows for telekinetically lifting the two atlas Mechs and slamming them at each other until they explode.

In fear of getting killed, the commander orders his surviving troops to retreat and they started running. But Arthur aimed his palm at them and spawned a completely black globe in his palm which sucks the fleeing troopers in such great force. After that he sensed the presence of Dr. Smythe; his doctor and 2 biotics on the balcony behind him. He turned and faced them; he removed his black hood and saw a man and a woman with Dr. smythe

Miranda and Shepard saw their sons face. He has his mother's nose and ears and his father's eyes and mouth. His skin was a mix of theirs.

"I can see in your eyes that you are wondering who are these two people near me, they are your parents Arthur L. Shepard or should I say Alpha-Omega" Dr. Smythe said.


	2. EXODUS

**Exodus**

"alpha-omega" Shepard wondering why was his son called that. "It's because he is the first and last, or to be accurate the only Trans-biotic being existing in this world"smythe explained

Arthur jumps to the balcony and faced Smythe "I know about them Doc., my grandfather told me"

"Arthur, we're glad to meet you" Shepard said "what is your age my boy" Miranda said eager to know more about her son. "17" he said.

Suddenly they felt the station tremble, Shepard contacted legion via Omni-tool "legion, what's happening?"

"Cerberus bombers known are destroying the facility by bombardment due to the absence of a self-destruct mechanism"

"Shit, we need to get out of here before this place blows" Shepard said as he and the others head back to the room where they left kasumi, thane, Oriana and the survivors"

"All of you follow me, we need to get to the Kodiak ASAP" he said as the others followed him to the elevator. Shepard pressed the button to the hangar.

"joker, bring the Normandy close to the hangar doors and guard us until we safely board the Normandy" he said before entering the elevator.

While waiting kasumi and garrus were asking questions about Arthur.

"Shep, I've heard gunfire's, explosions and screaming in there, did he did it?" kasumi questioned "yes, he slaughtered them all" Shepard replied

"Those biotic abilities, were those the abilities given by the L9z implant doctor?" garrus asked to Smythe "yes, but there are many more than anyone can imagine" the elevator stopped and doors opened.

They walked down the hangar using the stairs with shepard, Miranda and arthur are in the front while kasumi, thane and Miranda are behind the survivors who are between them and runs toward the Kodiak they used to enter the facility.

Suddenly, the floor near Shepard's foot was lashed by something blue which leaves a burned mark which causes him to order his squad to stop moving and scanned his surroundings for the origins of the attack. The others do the same. Shepard aimed his head and gun to the left; slowly but alert. A blue biotic whip appeared from the darkness which attempts to lash Shepard's head; no one noticed this but Arthur, who quickly withdraws his sword and slashes the whip just in time before it struck his father's head; which redirects it into hitting a crate on the left which was on Shepard's view. The whip was pulled back to the darkness

They all aimed their weapons at the location it was pulled after being alerted by that sound. Moments later a figure stepped out of the darkness; it was a Cerberus operative.

Smythe suddenly remembered something about that soldier "commander I forgot to tell you something, in the past we massed produced a prototype version of that implant; the L9a, it is weaker than the L9z but was easy and inexpensive to build. We implanted it to a volunteer who granted him new biotic abilities, and then we send all of the implants to the illusive man by his request and continue our research towards the real L9z"

"Doc you mean that, this thing in front of us has that" Arthur asked

"Yes arthur, the biotics who has those implants are called Templars" Smythe said

The Templar creates a sword of pure biotic energy on his palm. They aimed their weapons at him but Arthur tells them to lower their weapons

"it's my fight" Arthur said as he charges his katana with biotic while his blue violet aura was shown. The Templar also does the same.

They charged at each other at the same time which summons a large biotic blast; knocking back everyone except them. They exchanged blows but were always parried by one another. The Templar transforms his biotic sword to a whip and grabs a missile nearby and throws it at Arthur. Arthur's accelerated vision allowed him to slice the missile without making it explode and proceeds to attack the Templar. He held his sword up high and slams it at the Templar which is enough to cut him in half. After landing they embarked the Kodiak to finally escape the facility and return to the Normandy.

Joker sees a Kodiak nearing the Normandy and opens the hatch of the hangar

"Joker head to illium, my son says that it's important"

"Copy that commander, we'll be there in an hour" he said as he returns to the mass relay the previously used.

At the Cronos station, the illusive man is dismayed due to the failed attempt to retrieve Alpha-Omega; which he would use to destroys the enemies of Cerberus and ascend humanity.

"Sir its ready for the field test" a scientist spoke

"Show me" he said as he grabs his cigarette while opening his computer. He knows that the citadel council are improving their militaries to ensure peace and order to its territory, so that is why he commenced Project Orion; which will lead to the creation of a new Mech that will change the ways of warfare.

Seconds later after the video ended, he was amazed by its performance in battle.

"The test is successful, construct a 2 daily" he said to the chief engineer in the factory of the station, he wanted to have them build many at once, however it costs 10 million credits each and Cerberuses daily income from its wealthy sympathizers and front corporations is 100 million credits per week.

He turned off his computer and enjoyed the view of the sun in front of him.

**A/N: Sorry this chap. Is short. I spent most days debating if I would write a story in highschool dxd**


	3. ALTERATION

**ALTERATION**

Hours have passed since the rescue. With plenty of time before going to illium, Shepard and Miranda introduced their son Arthur to the crew and toured him at the Normandy. He took an interest in his father's pet varren named Urz. His father told him that urz became loyal to him upon feeding his with Pyjak Meat. His father gave him a vacant room in the Crews quarters to stay.

The next day when he awoke, he found Urz in a corner of his room staring at him. Arthur got confused, wondering how a varren did got into his room.

"Urz, why are you here?" he asked

The varren approaches him while whimpering.

Arthur immediately taught of what does he want, he placed his hand on Urzes head and rubs it. The varren closes his eyes in satisfaction, finding out that his masters son also likes him.

Arthur has finally found what he is looking for; the user for the device he made, a loyal creature.

**3 HOURS LATER**

They arrived in illiums orbit. All of the crew looks at the newly installed screen just above the galaxy map. Shepard, Miranda and Arthur were standing in the control panel of the galaxy map, most has been wondering why Arthur wants to go to illium. Suddenly an asari appeared in screen, which happens to be the person working for Arthur. She was in her middle maiden stage and appears to be wearing a scientist uniform.

"Doctor Al'zoma, it has been a long time since we met" Arthur said at the asari

"Only a week mister Arthur, I can see that your parents got you out" she said upon seeing commander shepard and Miranda Lawson.

"Enough talk, do you have it" Arthur said referencing at the object he wants

She lifts her right hand which was carrying a tube with a glowing violet fluid inside. Most crew immediately thought it's an element zero.

"impatient are you" al'zoma said "here is the substance containing the DNA of 100+ prehistoric or extinct deadly predators of all past and present civilizations, just pour all of this in that device and the user can transform into any species, but be warned for it will only work on non-sapient beings"

The reaction of the whole crew was universal

"WHAT!"

They were in awe, surprise or shock after learning that that fluid contains the essence of extinct predators.

"thank you for your help Al'zoma here is your reward" Arthur said while his eyes glows blue as he teleports a tube with a blue fluid "just as you requested, the cure for the Ardat-Yakshi" he teleports the other tube in his arm.

"thank you for accepting my request mister Arthur, with this no asari shall be feared or discriminated by their fellow asari" an overjoyed al'zoma said before ending the transmission. Everyone was amazed of Arthur because he created what is thought to be impossible; a cure for the Ardat-Yakshi. The salarian doctor Mordin asks if a cure for the krogan genophage is possible.

"I never made one yet, but it's possible" he replied which made mordin and grunt smile

Arthur looks at the tube he's holding and pulls out a hexagon shaped object with a jaw symbol and a blue and black color scheme. He opened the object and poured the substance inside until the last drop.

After that, he got down the control panel and walks to Urz, who was beside legion scratching his head with his feet. The whole crew finally knew what he is going to do; he is going to place that device on urz

He kneels and places the device in the varrens forehead "once it's placed in a suitable organism, it will merge with its skull" Arthur explained. Shepard was becoming anxious for his pets sake.

Arthur gets up and stands again and opens his omni-tool, then a button appeared with a text above it saying "activate Gene Alterer" he presses the button and the device on Urzs head glows blue, which made the entire crew slowly move back.

A pictures of the species in the substance appeared in his Omnitool, it includes their names and preys. He scrolls down and finds the Vorcha's extinct predator; Aptosaur and clicks it.

Urz body began to change as he began to increase in size; his teeth becomes larger, his mouth wider, 2 eyes erupted behind each of his eyes which made a right triangle position, his body becomes muscular, longer and develops green thick scales, his tail is longer and has a very sharp blade in the tip, his nose disappears and gills appears on his neck and his quills disappears. Now his body height was just like of shepards.

"this is what the Gene Alterer can do everyone" Arthur said to the crew, most of them especially grunt were terrified in urzs new form. Grunt can feel that he is experiencing fear.

Urz lets out a terryfing roar which was enough to knock grunt due to fear


	4. Sigurd

**Sigurd**

"GRUNT!" shepard yelled as he ran to his unconscious crewmate "what happened?" he asked his son.

"i forgot to say some thing about this creature" arthur points his finger to Urz who was still in his Aptosaur form "aptosaurs eyes can generate images of its preys fears upon direct eye contact this is used to render their prey easy to kill"

"so you mean" tali said

"yes, grunt fainted because urz manifested his fears upon direct eye contact" arthur said while pressing the "return to normal button" which returns Urz to his varren form

arthur then walks to grunt and places his left hand to grunts forehead "what are you doing?" asked his father

"checking what this krogan is afraid of" arthur said as his palm and eyes glows blue. moments later he removed his hand from the krogans head

"what did you see" asked thane

"he's afraid of Flesh Mites"

"whats that"asked shepard

"flesh mites are parasitic beings that lives inside the bodies krogans" the mordin said as he opens his omni tool and shows then the image of flesh mites;it was like a lice but has a red skin with ten small but sharp teeths "in infancy they feed on blood but upon maturity they start to consume the host from the inside then after that they find hosts to lay their eggs or keep hunting any krogan"

suddenly a bang was felt by everyone making them lose their balance.

"commander something penetrated the hull in the hangar you better check it out" says joker who was on the speakers

**5 minutes later**

shepard along with all of his squadmates with the exception of grunt arrives at the hangar only to see a huge mech; it was a meter taller than the ATLAS but it was like a heavily armored human with a long and massive black sword.

arthur sees its name on its chest "**Sigurd**"

"the illusive man sends his regards" the pilots said in the speakers as everyone is ready to fight


End file.
